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1.
Cancers (Basel) ; 14(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35804963

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICI) are currently the first-line treatment for patients with metastatic melanoma. We investigated the value of positron emission tomography (PET) response criteria to assess the therapeutic response to first-line ICI in this clinical context and explore the potential contribution of total tumor metabolic volume (TMTV) analysis. METHODS: We conducted a retrospective study in patients treated with first-line ICI for advanced or metastatic melanoma, with 18F-FDG PET/CT performed at baseline and 3 months after starting treatment. Patients' metabolic response was classified according to PERCIST5 and imPERCIST 5 criteria. TMTV was recorded for each examination. RESULTS: Twenty-nine patients were included. The median overall survival (OS) was 51.2 months (IQR 13.6-not reached), and the OS rate at 2 years was 58.6%. Patients classified as responders (complete and partial response) had a 90.9% 2-year OS rate versus 38.9% for non-responders (stable disease and progressive disease) (p = 0.03), for PERCIST5 and imPERCIST 5 criteria. The median change in metabolic volume was 9.8% (IQR -59-+140%). No significant correlation between OS and changes in TMTV was found. CONCLUSION: The evaluation of response to immunotherapy using metabolic imaging with PERCIST5 and imPERCIST5 was significantly associated with OS in patients with advanced or metastatic melanoma.

2.
Phys Med ; 57: 137-144, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30738517

RESUMEN

PURPOSES: The introduction of digital breast tomosynthesis (DBT) into the French breast cancer screening program is forecast by the authorities. The aim of the present study was to evaluate image quality phantoms to be used as internal quality controls. METHODS: Seven breast phantoms dedicated to quality control in mammography were evaluated on reconstructed DBT images: ACR Model 015, BR3D, DBT QC model 021, Mam/Digi-EPQC, MTM100, TOMOMAM® and TOMOPHAN®. Two representative image parameters of DBT images were studied: image score and z-resolution, when inserts were included in the phantom, on five DBT systems of three different brands. Three observers were involved. RESULTS: The MTM100, Mam/Digi-EPQC, BR3D, DBT QC model 021 phantoms' images presented artefacts affecting the image score. The ACR Model 015, TOMOMAM® and TOMOPHAN® phantoms appeared to be pertinent for DBT image score analysis. Due to saturation artefacts, Z-resolution results were not coherent with the theory for all phantoms except by using aluminium beads in the TOMOMAM® phantom. CONCLUSIONS: Phantom manufacturers should be encouraged to collaborate with DBT system manufacturers in order to design universal phantoms suitable for all systems for more complete quality control. From our study we can propose several specifications for an ideal and universal phantom designed for internal quality control in DBT. Phantoms should allow sensitive image score measurements. The background structure should be realistic to avoid artefacts. Phantoms should have a standard breast-like shape and size.


Asunto(s)
Mamografía/instrumentación , Fantasmas de Imagen , Control de Calidad
3.
Eur J Nucl Med Mol Imaging ; 44(7): 1145-1154, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28188325

RESUMEN

PURPOSE: The study was designed to evaluate 1) the relationship between PET image textural features (TFs) and SUVs, metabolic tumour volume (MTV), total lesion glycolysis (TLG) and tumour characteristics in a large prospective and homogenous cohort of oestrogen receptor-positive (ER+) breast cancer (BC) patients, and 2) the capability of those parameters to predict response to neoadjuvant chemotherapy (NAC). METHODS: 171 consecutive patients with large or locally advanced ER+ BC without distant metastases underwent an 18F-FDG PET examination before NAC. The primary tumour was delineated with an adaptive threshold segmentation method. Parameters of volume, intensity and texture (entropy, homogeneity, contrast and energy) were measured and compared with tumour characteristics determined on pre-treatment breast biopsy (Wilcoxon rank-sum test). The correlation between PET-derived parameters was determined using Spearman's coefficient. The relationship between PET features and pathological findings was determined using the Wilcoxon rank-sum test. RESULTS: Spearman's coefficients between SUVmax and TFs were 0.43, 0.24, -0.43 and -0.15 respectively for entropy, homogeneity, energy and contrast; they were higher between MTV and TFs: 0.99, 0.86, -0.99 and -0.87. All TFs showed a significant association with the histological type (IDC vs. ILC; 0.02 < P < 0.03) but didn't with immunohistochemical characteristics. SUVmax and TLG predicted the pathological response (P = 0.0021 and P = 0.02 respectively); TFs didn't (P: 0.27, 0.19, 0.94, 0.19 respectively for entropy, homogeneity, energy and contrast). CONCLUSIONS: The correlation of TFs was poor with SUV parameters and high with MTV. TFs showed a significant association with the histological type. Finally, while SUVmax and TLG were able to predict response to NAC, TFs failed.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Receptores de Estrógenos/metabolismo , Carga Tumoral , Adulto , Anciano , Transporte Biológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante
4.
Breast Cancer Res ; 19(1): 3, 2017 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-28057031

RESUMEN

BACKGROUND: This study investigated the value of some clinicopathological parameters and 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography (18FDG-PET/CT) indices, including textural features, to predict event-free survival (EFS) in estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) locally advanced breast cancer (BC) patients. METHODS: FDG-PET/CT indices and clinicopathological parameters were assessed before neoadjuvant chemotherapy (NAC). After completion of chemotherapy, all patients had breast surgery with axillary lymph node dissection, followed by radiation therapy and endocrine therapy for 5 years. EFS was estimated using the Kaplan-Meier method. A Cox proportional hazard regression model was used for multivariate analysis. RESULTS: One hundred forty-three consecutive patients with stage II-III ER+/HER2- BC and without distant metastases at baseline PET were included. High standardized uptake values (SUVs), were associated with shorter EFS (HR = 3.51, P < 0.01 for SUVmax; HR = 2.76, P = 0.02 for SUVmean; and HR = 4.40 P < 0.01 for SUVpeak). Metabolically active tumor volume (MATV, HR = 3.47, P < 0.01) and total lesion glycolysis (TLG, HR = 3.10, P < 0.01) were also predictive of EFS. Homogeneity was not predictive (HR = 2.27, P = 0.07) and entropy had weak prediction (HR = 2.89, P = 0.02). Among clinicopathological parameters, EFS was shorter in progesterone receptor (PR)-negative tumor (vs. PR-positive tumor; HR = 3.25, P < 0.01); histology was predictive of EFS (lobular vs. ductal invasive carcinoma; HR = 3.74, P = 0.01) but not tumor grade (grade 3 vs. grade 1-2; HR = 1.64, P = 0.32). Pathological complete response after NAC was not correlated to the risk of relapse. Three parameters remained significantly associated with EFS in multivariate analysis. MATV (HR = 1.01, P < 0.01), progesterone receptor expression (HR = 2.90, P = 0.03) and tumor histology (HR = 3.80, P = 0.02). CONCLUSIONS: Baseline PET parameters measured before neoadjuvant treatment have prognostic values in ER+/HER2- locally advanced breast cancer patients. After multivariate analysis, metabolically active tumor volume remains significant while textural analysis of PET images is not of added value. Considering histopathological parameters, our study shows that patients with PR-negative or lobular invasive tumor have poorer prognosis than patients with PR-positive or ductal carcinoma, respectively.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/mortalidad , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , Anciano , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Evaluación del Resultado de la Atención al Paciente , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Pronóstico , Modelos de Riesgos Proporcionales , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Carga Tumoral
5.
Acad Radiol ; 23(10): 1246-54, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27346234

RESUMEN

RATIONALE AND OBJECTIVES: The study aimed to evaluate the performances of two iterative reconstruction (IR) algorithms and of filtered back projection (FBP) when using reduced-dose chest computed tomography (RDCT) compared to standard-of-care CT. MATERIALS AND METHODS: An institutional review board approval was obtained. Thirty-six patients with hematologic malignancies referred for a control chest CT of a known lung disease were prospectively enrolled. Patients underwent standard-of-care scan reconstructed with hybrid IR, followed by an RDCT reconstructed with FBP, hybrid IR, and iterative model reconstruction. Objective and subjective quality measurements, lesion detectability, and evolution assessment on RDCT were recorded. RESULTS: For RDCT, the CTDIvol (volumetric computed tomography dose index) was 0.43 mGy⋅cm for all patients, and the median [interquartile range] effective dose was 0.22 mSv [0.22-0.24]; corresponding measurements for standard-of-care scan were 3.4 mGy [3.1-3.9] and 1.8 mSv [1.6-2.0]. Noise significantly decreased from FBP to hybrid IR and from hybrid IR to iterative model reconstruction on RDCT, whereas lesion conspicuity and diagnostic confidence increased. Accurate evolution assessment was obtained in all cases with IR. Emphysema identification was higher with iterative model reconstruction. CONCLUSION: Although iterative model reconstruction offered better diagnostic confidence and emphysema detection, both IR algorithms allowed an accurate evolution assessment with an effective dose of 0.22 mSv.


Asunto(s)
Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Enfermedades Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad
6.
Eur J Nucl Med Mol Imaging ; 42(11): 1682-1691, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26140849

RESUMEN

PURPOSE: The aim of this retrospective study was to determine if some features of baseline (18)F-FDG PET images, including volume and heterogeneity, reflect clinical, histological or immunohistochemical characteristics in patients with stage II or III breast cancer (BC). METHODS: Included in the present retrospective analysis were 171 prospectively recruited patients with stage II/III BC treated consecutively at Saint-Louis hospital. Primary tumour volumes were semiautomatically delineated on pretreatment (18)F-FDG PET images. The parameters extracted included SUVmax, SUVmean, metabolically active tumour volume (MATV), total lesion glycolysis (TLG) and heterogeneity quantified using the area under the curve of the cumulative histogram and textural features. Associations between clinical/histopathological characteristics and (18)F-FDG PET features were assessed using one-way analysis of variance. Areas under the ROC curves (AUC) were used to quantify the discriminative power of the features significantly associated with clinical/histopathological characteristics. RESULTS: T3 tumours (>5 cm) exhibited higher textural heterogeneity in (18)F-FDG uptake than T2 tumours (AUC <0.75), whereas there were no significant differences in SUVmax and SUVmean. Invasive ductal carcinoma showed higher SUVmax values than invasive lobular carcinoma (p = 0.008) but MATV, TLG and textural features were not discriminative. Grade 3 tumours had higher FDG uptake (AUC 0.779 for SUVmax and 0.694 for TLG), and exhibited slightly higher regional heterogeneity (AUC 0.624). Hormone receptor-negative tumours had higher SUV values than oestrogen receptor-positive (ER-positive) and progesterone receptor-positive tumours, while heterogeneity patterns showed only low-level variation according to hormone receptor expression. HER-2 status was not associated with any of the image features. Finally, SUVmax, SUVmean and TLG significantly differed among the three phenotype subgroups (HER2-positive, triple-negative and ER-positive/HER2-negative BCs), but MATV and heterogeneity metrics were not discriminative. CONCLUSION: SUV parameters, MATV and textural features showed limited correlations with clinical and histopathological features. The three main BC subgroups differed in terms of SUVs and TLG but not in terms of MATV and heterogeneity. None of the PET-derived metrics offered high discriminative power.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Fluorodesoxiglucosa F18 , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Carga Tumoral , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
7.
Radiology ; 277(2): 358-71, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25915099

RESUMEN

PURPOSE: To investigate parameters based on fluorine 18 fluorodeoxyglucose (FDG) positron emission tomographic (PET) imaging that are best correlated with pathologic complete response (PCR) in human epidermal growth factor receptor type 2 (HER2)-positive cancer and triple-negative breast cancer (TNBC) and with partial or complete response in ER-positive/HER2-negative breast cancer. MATERIALS AND METHODS: This study was approved by institutional review board with waivers of informed written consent and included consecutive patients treated by neoadjuvant chemotherapy. Five PET examination-derived parameters were tested: standard uptake value (SUV) maximum (SUV(max)), peak (SUV(peak)), and mean (SUV(mean)), metabolically active tumor volume, and total lesion glycolysis (TLG). Absolute values at baseline PET, at PET imaging after two cycles of chemotherapy, and variation (ie, change) were measured. Correlations with pathologic response (Wilcoxon rank-sum test) and predictive power assessed (area under the curve [AUC] on the basis of receiver operating characteristic analysis) were examined. RESULTS: Included were 169 consecutive patients (mean age, 50 years). PCR was more frequent in HER2-positive tumors (16 of 33 patients [48.5%]) and TNBCs (20 of 54 patients [37%]) than in ER positive/HER2-negative tumors (four of 82 [4.9%]) (P < .001). Among patients with ER-positive/HER2-negative cancers, 33 patients had partial response. In TNBC, best association with PCR was obtained with change in SUV(max) (AUC, 0.86) or change in TLG (AUC, 0.88). In HER2-positive phenotype, absolute SUV(max) (or SUV(peak)) values at PET imaging after two cycles of chemotherapy (AUC for each cycle, 0.93) were better correlated with PCR than change in SUV(max) (AUC, 0.78; P = .11) or change in TLG (AUC, 0.62; P = .005). Regarding ER-positive/HER2-negative cancers, change in SUV(max) or change in TLG (AUC, 0.75) were parameters best correlated with partial or complete response. Baseline SUV(max) was higher in lymph nodes than in primary tumor in 31 patients. Findings were similar considering the site with highest FDG uptake. CONCLUSION: Quantitative indexes of tumor glucose use that are best correlated with pathologic response vary by phenotype: change in SUV(max) or TLG are most adequate for TNBCs and ER-positive/ HER2-negative cancers and absolute SUV(max) after two cycles of chemotherapy for HER2-positive breast cancers.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Imagen Multimodal , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biopsia con Aguja Gruesa , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Humanos , Hibridación in Situ , Escisión del Ganglio Linfático , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Radiofármacos/farmacocinética , Estudios Retrospectivos , Riesgo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
8.
J Nucl Med ; 56(1): 38-44, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25500829

RESUMEN

UNLABELLED: Intratumoral uptake heterogeneity in (18)F-FDG PET has been associated with patient treatment outcomes in several cancer types. Textural feature analysis is a promising method for its quantification. An open issue associated with textural features for the quantification of intratumoral heterogeneity concerns its added contribution and dependence on the metabolically active tumor volume (MATV), which has already been shown to be a significant predictive and prognostic parameter. Our objective was to address this question using a larger cohort of patients covering different cancer types. METHODS: A single database of 555 pretreatment (18)F-FDG PET images (breast, cervix, esophageal, head and neck, and lung cancer tumors) was assembled. Four robust and reproducible textural feature-derived parameters were considered. The issues associated with the calculation of textural features using co-occurrence matrices (such as the quantization and spatial directionality relationships) were also investigated. The relationship between these features and MATV, as well as among the features themselves, was investigated using Spearman rank coefficients for different volume ranges. The complementary prognostic value of MATV and textural features was assessed through multivariate Cox analysis in the esophageal and non-small cell lung cancer (NSCLC) cohorts. RESULTS: A large range of MATVs was included in the population considered (3-415 cm(3); mean, 35; median, 19; SD, 50). The correlation between MATV and textural features varied greatly depending on the MATVs, with reduced correlation for increasing volumes. These findings were reproducible across the different cancer types. The quantization and calculation methods both had an impact on the correlation. Volume and heterogeneity were independent prognostic factors (P = 0.0053 and 0.0093, respectively) along with stage (P = 0.002) in non-small cell lung cancer, but in the esophageal tumors, volume and heterogeneity had less complementary value because of smaller overall volumes. CONCLUSION: Our results suggest that heterogeneity quantification and volume may provide valuable complementary information for volumes above 10 cm(3), although the complementary information increases substantially with larger volumes.


Asunto(s)
Fluorodesoxiglucosa F18/metabolismo , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Tomografía de Emisión de Positrones , Carga Tumoral , Transporte Biológico , Estudios de Cohortes , Humanos , Neoplasias/metabolismo , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia
9.
Cancer ; 119(11): 1960-8, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23504954

RESUMEN

BACKGROUND: The objective of this prospective study was to evaluate the ability of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) to predict chemosensitivity in patients with estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer. METHODS: Sixty-four consecutive patients underwent (18)F-FDG PET/CT scanning at baseline and after the second course of neoadjuvant chemotherapy (NAC). The evolution (Δ) between the 2 scans of image parameters (maximum standardized uptake value [SUV(max)], SUV(mean), metabolic tumor volume, and total lesion glycolysis [TLG]) was measured. Correlations between early changes in PET-derived parameters and pathologic response observed in surgical specimens after the completion of 8 courses of NAC were estimated with Mann-Whitney U tests. Response prediction on the basis of clinical data, histologic type, or molecular markers also was assessed (Fisher exact test). Receiver operating characteristic (ROC) analysis was used to compare the area under the curve (AUC) of each parameter. RESULTS: The best prediction of chemosensitivity was obtained with ΔTLG (-49% ± 31% in nonresponders vs -73% ± 25% in responders; P < .0001). Among the biologic parameters, only negative progesterone receptor status (57% responders vs 31% nonresponders; P = .04) and luminal B subtype (63% responders vs 22% nonresponders; P = .02) were predictive of a pathologic response. ROC analysis resulted in an AUC of 0.81, 0.73, 0.71, and 0.63 for ΔTLG, ΔSUV(max), luminal subtype, and progesterone receptor status, respectively. CONCLUSIONS: When patients responded to NAC, the majority of ER-positive/HER2 negative tumors exhibited partial tumor shrinkage; and the PET parameters that combined volume and activity measurements, such as TLG, offered better accuracy for early prediction than the SUV(max). Negative progesterone receptor status and luminal B subtype had weaker predictive power than PET-derived parameters.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Fluorodesoxiglucosa F18 , Radiofármacos , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Femenino , Humanos , Persona de Mediana Edad , Imagen Multimodal/métodos , Terapia Neoadyuvante , Tomografía de Emisión de Positrones , Estudios Prospectivos , Tomografía Computarizada por Rayos X/métodos
10.
PLoS One ; 8(3): e58152, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23516443

RESUMEN

UNLABELLED: A multi-centre trial using PET requires the analysis of images acquired on different systems We designed a multi-centre trial to estimate the value of 18F-FLT-PET to predict response to neoadjuvant chemotherapy in patients with newly diagnosed breast cancer. A calibration check of each PET-CT and of its peripheral devices was performed to evaluate the reliability of the results. MATERIAL AND METHODS: 11 centres were investigated. Dose calibrators were assessed by repeated measurements of a 68Ge certified source. The differences between the clocks associated with the dose calibrators and inherent to the PET systems were registered. The calibration of PET-CT was assessed with an homogeneous cylindrical phantom by comparing the activities per unit of volume calculated from the dose calibrator measurements with that measured on 15 Regions of Interest (ROIs) drawn on 15 consecutive slices of reconstructed filtered back-projection (FBP) images. Both repeatability of activity concentration based upon the 15 ROIs (ANOVA-test) and its accuracy were evaluated. RESULTS: There was no significant difference for dose calibrator measurements (median of difference -0.04%; min = -4.65%; max = +5.63%). Mismatches between the clocks were less than 2 min in all sites and thus did not require any correction, regarding the half life of 18F. For all the PET systems, ANOVA revealed no significant difference between the activity concentrations estimated from the 15 ROIs (median of difference -0.69%; min = -9.97%; max = +9.60%). CONCLUSION: No major difference between the 11 centres with respect to calibration and cross-calibration was observed. The reliability of our 18F-FLT multi-centre clinical trial was therefore confirmed from the physical point of view. This type of procedure may be useful for any clinical trial involving different PET systems.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Didesoxinucleósidos , Radioisótopos de Flúor , Imagen Multimodal/normas , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Análisis de Varianza , Neoplasias de la Mama/tratamiento farmacológico , Calibración , Femenino , Humanos , Imagen Multimodal/instrumentación , Control de Calidad , Reproducibilidad de los Resultados
11.
J Nucl Med ; 54(3): 341-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23327900

RESUMEN

UNLABELLED: The goal of this study was to determine the best predictive factor among image-derived parameters extracted from sequential (18)F-FDG PET scans for early tumor response prediction after 2 cycles of neoadjuvant chemotherapy in breast cancer. METHODS: 51 breast cancer patients were included. Responder and nonresponder status was determined by histopathologic examination according to the tumor and node Sataloff scale. PET indices (maximum and mean standardized uptake value [SUV], metabolically active tumor volume, and total lesion glycolysis [TLG]), at baseline and their variation (Δ) after 2 cycles of neoadjuvant chemotherapy were extracted from the PET images. Their predictive value was investigated using Mann-Whitney U tests and receiver-operating-characteristic analysis. Subgroup analysis was also performed by considering estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative, triple-negative, and HER2-positive tumors separately. The impact of partial-volume correction was also investigated using an iterative deconvolution algorithm. RESULTS: There were 24 pathologic nonresponders and 27 responders. None of the baseline PET parameters was correlated with response. After 2 neoadjuvant chemotherapy cycles, the reduction of each parameter was significantly associated with response, the best prediction of response being obtained with ΔTLG (96% sensitivity, 92% specificity, and 94% accuracy), which had a significantly higher area under the curve (0.91 vs. 0.82, P = 0.01) than did ΔSUVmax (63% sensitivity, 92% specificity, and 77% accuracy). Subgroup analysis confirmed a significantly higher accuracy for ΔTLG than ΔSUV for ER-positive/HER-negative but not for triple-negative and HER2-positive tumors. Partial-volume correction had no impact on the predictive value of any of the PET image-derived parameters despite significant changes in their absolute values. CONCLUSION: Our results suggest that the reduction after 2 neoadjuvant chemotherapy cycles of the metabolically active volume of primary tumor measurements such as ΔTLG predicts histopathologic tumor response with higher accuracy than does ΔSUV measurements, especially for ER-positive/HER2-negative breast cancer. These results should be confirmed in a larger group of patients as they may potentially increase the clinical value and efficiency of (18)F-FDG PET for early prediction of response to neoadjuvant chemotherapy.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Fluorodesoxiglucosa F18 , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama/metabolismo , Estudios de Cohortes , Femenino , Radioisótopos de Flúor , Humanos , Terapia Neoadyuvante , Neoplasias Hormono-Dependientes/diagnóstico por imagen , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/metabolismo , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radiofármacos , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos , Resultado del Tratamiento
12.
Clin Nucl Med ; 36(8): 665-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21716017

RESUMEN

Perfusion brain single photon emission computed tomography (SPECT) is currently used to evaluate patients with cognitive impairments. Although widely available, it has been reported to be significantly less sensitive than F-18 FDG positron emission tomography. Optimization of SPECT parameters using nonuniform attenuation correction (NUAC) and scatter correction (SC) might improve the accuracy of the method. This study assessed the effect of x-ray CT-based NUAC and triple-energy window (TEW-SC) on brain SPECT compared with Chang-uniform (UAC). A total of 31 patients with memory complaints underwent Tc-99m ECD SPECT/CT. CT-NUAC+TEW-SC and Chang-UAC were applied and compared. The images were spatially normalized to a default SPECT template supplied with Statistical Parametric Mapping software (SPM2). A paired t test image was then reconstructed. Regional cerebral blood flow measurements were apparently reduced in the frontal white-matter and in the frontotemporal cortex when CT-NUAC+TEW-SC were used. These findings need to be considered when interpreting Tc-99m ECD SPECT after applying CT-AC+TEW-SC. Further prospective studies with clinical correlations are needed.


Asunto(s)
Encéfalo/diagnóstico por imagen , Cisteína/análogos & derivados , Compuestos de Organotecnecio , Dispersión de Radiación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Encéfalo/fisiopatología , Femenino , Humanos , Masculino , Trastornos de la Memoria/diagnóstico por imagen , Trastornos de la Memoria/fisiopatología , Persona de Mediana Edad , Estudios Retrospectivos
13.
Nucl Med Commun ; 30(12): 926-33, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19574939

RESUMEN

PURPOSE: We tested the impact of different values of the relaxation parameter lambda (lambda) on contrast and noise in line-of-response row-action maximum likelihood algorithm (LOR-RAMLA) in 18F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) imaging. METHODS: Phantom studies were performed on a Gemini XL PET/CT scanner. The NEMA/IEC (National Electrical Manufacturers Association/International Electro technical Commission) torso phantom was used and acquisition data were reconstructed with lambda values ranging from 0.025 to 0.1. Quality of the reconstructed images was evaluated by contrast recovery coefficients and background variability values according to the NEMA NU 2-2001 procedures. RESULTS: Contrast recovery coefficients and background variability increased significantly when lambda increased. The best noise-versus-resolution trade-off was obtained with lambda in the 0.04-0.06 range. For LOR-RAMLA reconstruction, the manufacturer allows a possible lambda choice from 0.025 to 0.1. We would not advise too small (0.025) or too large (0.1) lambda values which result in too smooth or too noisy images. CONCLUSION: We determined optimal lambda values in LOR-RAMLA on a Gemini XL PET/CT scanner. Caution is needed when using lambda values out of that range.


Asunto(s)
Algoritmos , Fluorodesoxiglucosa F18 , Interpretación de Imagen Asistida por Computador/métodos , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Humanos , Funciones de Verosimilitud , Neoplasias Pulmonares/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Fantasmas de Imagen , Control de Calidad
14.
Cancer Biol Ther ; 6(1): 56-61, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17172819

RESUMEN

We sought to investigate the apoptosis-inducing activities of quercetin, Siamois 1, and Siamois 2 against invasive estrogen-receptor negative MDA-MB 435 cells xenografted in athymic nude mice. This study clearly demonstrated that these compounds exhibited apoptosis-inducing activities in cell culture system. Quercetin (20 microg/mL), Siamois 1 (100 microg/mL), and Siamois 2 (200 microg/mL) can induce apoptotic cell death by 40 +/-5%, 44 +/- 14 %, and 31 +/- 13 %, respectively. Two-fold of IC50 of these compounds were clearly found to induce apoptosis in breast tumor tissue which can be determined by 99mTc-Annexin V scintigraphy and histological staining. This is the first report that the apoptosis-inducing effects of quercetin, Siamois 1 and Siamois 2 on the MDA-MB 435 cell in vitro were effectively extrapolated to the in vivo situation. These compounds might be considered as a simple dietary supplement and with further clinical investigation for their use as a nutrition-based intervention in breast cancer treatment.


Asunto(s)
Apoptosis , Neoplasias de la Mama/patología , Quercetina/análogos & derivados , Quercetina/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Ratones , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
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